4 Hz oscillations and 30 Hz oscillations have been observed in real world wind farms connected to weak grid power systems. Stability issues caused by these occurrences can limit the efficiency of the delivery of wind-based energy to a power grid.
Weak grid stability of power systems can be due to the coupling of the power delivery and the voltage at the point of common coupling (PCC). Increasing the power delivery can lead to a reduction in the PCC voltage and lead to instability in weak grid power systems. By reducing the instability in a weak grid power system, the delivery efficiency to a power grid can be enhanced.